There are numerous risk factors and causes of
cancer. Among them are age, sex, and family medical
history. Some risk factors depend on the type of cancer.
In some cases, a person may have more than one
risk factor for the disease. Another person may be
diagnosed with cancer and have no apparent risk factor.
Genetic causes can’t be controlled by an individual,
but people who know they are at risk because a
close relative had a particular cancer should follow all
recommendations for screening and prevention.
Often, physicians cannot explain what causes cancer.
In addition to a family history of cancer, overall
risk factors for cancer include aging, tobacco or alcohol
use, exposure to sunlight or ionizing radiation,
exposure to certain chemicals or substances, and exposure
to some viruses and bacteria.
Poor diet, lack of
physical activity, or being overweight also are risk
factors for cancers. Not all of these risk factors pertain
to all cancers. For example, exposure to sunlight is a
risk factor for skin cancer, while certain hormones
increase the risk of breast cancer.
Cancer may not produce pain. And many symptoms
may be due to a condition that is not cancer. But
any signs similar to those for a particular cancer or
that show a change in health should be checked by a
physician.
Symptoms vary depending on the type of
cancer, but some common symptoms of cancer
include:
-feeling weak or very tired
-a lump in the breast or any other part of the body
-a new mole or changes in an existing mole
-changes to bowel or bladder habits
-hoarseness or a cough that won’t go away
-a sore that doesn’t heal
-difficulty swallowing
-unexplained weight loss or weight gain
-unusual discharge or bleeding
